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Locos going only right-to-left...no reverse

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Posted by wjstix on Friday, March 9, 2018 7:54 AM

I'd go simple. Put the engine on a piece of track. Connect two wires to the "DC Variable" output of one power pack. With your hands, touch one wire to one rail and the other wire to the other rail with the power on say half way. If the engine moves, reverse the wires (NOT the power pack) that you're holding on the track. If the engine moves the opposite way now, then the engine is fine. Then try the same thing after moving the reverse switch to the other setting. If the engine goes forward and then back, then the problem is the wiring on your layout.

Stix
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Posted by mbinsewi on Friday, March 9, 2018 7:49 AM

rrinker
Before you do anything else, take some spare sections of track and hook the power pack to them, and see if the loco runs there in both directions. If it works fine that way, then the problem is in how the rest of the layout is wired.

Best advice yet, after stopping the video a bunch of times, and looking at the track layout.  And check out the hammer laying on the track, right at the beginning.

Mike.

 

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Posted by rrinker on Friday, March 9, 2018 7:20 AM

 In the video, does it stop there by itself or are you turning the speed control off?

Even if the direction switch was defective, if it was not touched but the loco turned around, it should run. 

It also looks like there may be a reverse loop in that layout - how is that being handled?

Before you do anything else, take some spare sections of track and hook the power pack to them, and see if the loco runs there in both directions. If it works fine that way, then the problem is in how the rest of the layout is wired.

                                           --Randy

 


Modeling the Reading Railroad in the 1950's

 

Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.

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Posted by mbinsewi on Friday, March 9, 2018 7:05 AM

The OP said in his first post that he also has an Athearn power pack.  Maybe try that.

Mike.

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Posted by richhotrain on Friday, March 9, 2018 5:33 AM

Ajhall

A quick note: The YouTube link should be fixed now. Again, the url is https://youtu.be/Tn2oueQro1c  

After watching that video a few times, I am convinced that something is wrong with the directional switch on the power pack. 

I have several of the MRC Railpower 1370s to power signals and Tortoises on my DCC layout.  They are pretty darn reliable and rugged. But, that doesn't mean that something cannot be sticking on the directional slide switch.  Mess with it, jiggle it back and forth, and see if that helps.

Rich

Alton Junction

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Posted by Ajhall on Friday, March 9, 2018 5:13 AM

A quick note: The YouTube link should be fixed now. Again, the url is https://youtu.be/Tn2oueQro1c 

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Posted by rrebell on Thursday, March 8, 2018 9:52 PM

sounds like an insolated joiner missing with that slowing away from the pack, seen that before, just enough power going through things to muck it up but not enough to trip the breaker.

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Posted by BigDaddy on Thursday, March 8, 2018 9:31 PM

Ajhall
Which leads to loco #2, which I was unable to video when I ran the test on it. It's an old Athearn I bought on eBay, another GP9 in the Boston & Maine paint scheme. I know it's DC only. It runs fine, I've never had trouble with it. I got exactly the same results with it that I did with the Bachmann on the video.

That blows my decoder theory out of the water.

Your slowing at the far end of the layout is probably a function of poor conductivity between the rail joiners.  We can tell you how to fix that later, the current problem is more pressing.

 

Henry

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Posted by ricktrains4824 on Thursday, March 8, 2018 8:57 PM

AJ -

It matters, but it doesn't matter, which wire goes to which terminal.

One rail, goes to one of the variable DC terminals, the other rail goes to the other variable DC terminal.

Make sure that the wires do not touch each other, or any other terminals. (Especially the accessories terminals.) 

If the wires are hooked up correctly, at full throttle you will get somewhere close to 15V DC, on both direction settings. Your multimeter should say +15 V one way, and -15 V the other way. (This is correct.) 

Ricky W.

HO scale Proto-freelancer.

My Railroad rules:

1: It's my railroad, my rules.

2: It's for having fun and enjoyment.

3: Any objections, consult above rules.

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Posted by Ajhall on Thursday, March 8, 2018 8:37 PM

Tommorrow when I go down cellar again, I'll redo the wires (does it matter which DC screw the wires are attached to? Their polarity isn't noted.), and do a voltage test. No one will ever accuse me of being an electrician, and I treat electricity with the utmost respect -- not to say trepidation. I have a medical condition that messes with my fine motor skills, so detail things like twisting and attaching wires is something I do slowly. 

I'm going to try re-uploading the video. 

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Posted by BigDaddy on Thursday, March 8, 2018 8:29 PM

edit never mind, there wouldn't be a share button if it were a private video.

 

Henry

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Posted by ricktrains4824 on Thursday, March 8, 2018 7:42 PM

AJ -

I can't seem to be able to view your video. I get "Sorry, no videos."

However, based on what you just said, I see a couple of issues.

Both of your loco's have the same issue, so it is not a locomotive issue. This is helpful, as now we won't be wasting time checking the loco.

You also mentioned a second problem, that of the locomotives slowing farther from the power pack. You also have a current drop issue, however, I say also as this will not (most times) cause your other issue, of only working in one direction.

Really double check your wiring connections on your power pack. Make sure that both wires are connected, to the correct terminals. 

If you have a multimeter, it might be worthwhile to check your DC volt reading, with no loco on the track, on both direction settings.

Ricky W.

HO scale Proto-freelancer.

My Railroad rules:

1: It's my railroad, my rules.

2: It's for having fun and enjoyment.

3: Any objections, consult above rules.

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Posted by Ajhall on Thursday, March 8, 2018 7:20 PM

Phew! What I thought was a simple, even embarrassingly newbie a question is turning out to be challenging. To try to clarify, I managed to make a short video -- about a minute and a half, all I had the memory for -- demonstrating the problem and the power wiring set up. A couple of things to keep in mind:

  • Re: the loco. I bought it brand new from Trainworld. I chose the DCC equipped because, frankly, it was the only GP9 loco in the Bangor and Aroostook paint-scheme that I was able to afford, and the description clearly said it was DC-compatible.
  • Which leads to loco #2, which I was unable to video when I ran the test on it. It's an old Athearn I bought on eBay, another GP9 in the Boston & Maine paint scheme. I know it's DC only. It runs fine, I've never had trouble with it. I got exactly the same results with it that I did with the Bachmann on the video.
  • I double checked the track to make sure everything is connected -- I changed out a length that looked a bit too oxidized.
  • I am NOT touching anything else. The only thing hooked up to the track and plugged in is the power pack I was using as a test. 
  • I don't know if it matters, but it seems as if the locos slow down at the far reaches of the layout.

https://youtu.be/Tn2oueQro1c

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Posted by BigDaddy on Thursday, March 8, 2018 5:32 PM

steemtrayn
Remove the decoder and install a dummy plug. If it operates normally, then the decoder is the problem.

Do these Bachmann's have plugs?  For the OP, some DCC ready locos came with a plug with a "dummy plug" that could be replaced by a DCC decoder plug.  Not all OEM installed DCC decoders have plugs.

Maybe WHERE is a better question than WHY did he buy it.  If at a local train store, they could try it on their display track and reset the decoder.

 

Henry

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Posted by Ron High on Thursday, March 8, 2018 5:27 PM

I would get a couple of clip leads and  a short piece of track. Connect the power pack output for the track to this short piece of track . Try running these engines on this short piece of track with no connection to any other track or equipment. Try the reverse switch . This should give you some idea if it is the engines or power pack issues. Do this with both packs connecting and trying one at time.

Ron High

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Posted by wjstix on Thursday, March 8, 2018 3:51 PM

Ya, I bought a "DCC On Board" 45-tonner recently, and it indeed has a decoder installed...a pretty basic one, but it works fine.

Some more questions / thoughts for the OP....

Although there is an NMRA standard for which rail is positive and which is negative, it doesn't really matter. You can wire it up either way and the engines will work fine.

Is it possible you accidently hooked up one of the track connection wires to the 12V DC accessory output instead of having both go to the 12V DC variable outputs? (12V variable output is controlled by the throttle; the 12V DC accessory outputs are a constant full 12 volts - for like lights or switches.) If I'm thinking this through correctly, if you say have one rail connected the positive 12V DC variable output, and the other rail to the negative of the 12V, you'd have a situation where if you have the reverse switch set one way, the engine would get variable positive DC from one rail, and the constant negative through the other, which should allow the engine to run. Hit the reverse switch, and now the variable DC is negative, and the other rail hooked up to the negative constant DC is negative too - so nothing happens.

You don't by chance have both power packs hooked up at the same time? If they're not wired in correctly, with double-pole / double-throw switches to choose which block is controlled by which power pack, it could be causing trouble.

Stix
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Posted by zstripe on Thursday, March 8, 2018 3:47 PM

There could be nothing wrong with the reversing, other than dirty oxidized contacts. I have had that happen to a MRC 1500 once in awhile if not used for a long period. The slide switch contacts build up oxidation and do not make contact when you slide them. I have had to slide them back and forth a few times to wear off the oxidation. I do that to all the slide switches on the unit and then they will work normal again. I believe that unit also has a momentum switch, that will also happen to it, do that to the slide switch also. It will also lose contact and make sure it is off when testing.

Do That on a test track....as has been suggested and don't worry about what direction the engine is facing, if the switch is working, the engine will go forward, slide the switch the other way and it should go in reverse. If it will not do that on the layout....you have a wiring problem or no power to some sections of Your track. If just using a terminal joiner and rail joiners for power distribution, anything is possible.

Good Luck! Big Smile

Frank

 

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Posted by mbinsewi on Thursday, March 8, 2018 3:28 PM

I don't think it's been determined yet that it has a decoder in it.  His Bachmann GP9 has "DCC On Board", but it comes out of the package with dummy plugs, in DC mode.

Unless he bought this from a sale site, and the previous owner installed a decoder.  I asked him that in an earlier post, but I haven't gotten any answers.

I also asked him if the lights work in both direction, no answer yet.

Mike.

EDIT:  I'm probably wrong about this too, according to Bachmann, if this is a "DCC On Board", it's DCC out of the box.  I'll just go back to my corner Dunce

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Posted by richhotrain on Thursday, March 8, 2018 3:21 PM

steemtrayn

Remove the decoder and install a dummy plug. If it operates normally, then the decoder is the problem. 

Yeah, that's a good point. Why are you running a DCC equipped locomotive on a DC layout?

Rich

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Posted by steemtrayn on Thursday, March 8, 2018 3:13 PM

Remove the decoder and install a dummy plug. If it operates normally, then the decoder is the problem.

 

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Posted by richhotrain on Thursday, March 8, 2018 3:11 PM

Ajhall

Now, with the switch on the power pack to the left ("forward"), and the rear of the loco facing clockwise (left), the loco travels clockwise. When I flip it around so the front of the train is facing clockwise (left), nothing happens. When I move the switch to the right, and the front is still facing clockwise, nothing happens. When I flip the loco again (rear facing left), it moves to the left (clockwise).

Sounds like a power pack problem to me.

You say that with the switch on the power pack to the left (forward), the loco travels clockwise, then you flip it around and nothing happens.

How about trying this.

With the switch on the power pack to the left (forward), get the loco traveling clockwise, the flip it around and expect it do nothing. Slide the switch on the power pack to the right (reverse). Does anything happen? If not, slide the switch on the power pack back to the left (forward). Does anything happen? 

I am just wondering if the directional switch is stuck.

Rich

 

Alton Junction

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Posted by mbinsewi on Thursday, March 8, 2018 2:59 PM

Ya, I know, I thought of that after I left the house for a while.  Dunce  I was going to edit, but you already caught it. Laugh

Mike.

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Posted by rrinker on Thursday, March 8, 2018 2:39 PM

 If both pickups fell off the loco on one side, it wouldn't run at all. That does not seem to be the issue at all. It's as if the motor simply can not turn one way - if it runs with one combination fo facing a certain way AND the direction switch set one way, if the loco is physcially tuend around AND the direction switch flipped, then the motor would be turning the same way it was in the running configuration. Since that fails, I can only guess the direction switch is broken and no power gets to the rails. However, with the loco physically turned around but the direction switch untouched - the loco should move in the same physical direction as the working mode, except that it will be running 'backwards' relative to the cab position. Since that also does not work, it seems to rule out the direction switch. This is definitely a mystery, it makes no sense electrically. Unless there are actually two problme shere, one being a failed direction switch int he pwoer pack, the other being something wrong internally in the loco. Easily verified with a cheap digital meter set to DC volts. I just don't knwo what could make a loco alone behave like that -  only spin the motor in one direction, sure, lots of ways to mess up the internal wiring to make that happen. But turning the loco end for end on the rails AND flipping the direction switch does not change the direction the motor is trying to rotate.

                                        --Randy


Modeling the Reading Railroad in the 1950's

 

Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.

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Posted by mbinsewi on Thursday, March 8, 2018 1:42 PM

The Bachmann loco he is using for the test has the brass wipers.  What are the chances that both feeder wires from the wipers came off, on one side. Huh?

Although, it has happened to me, once, from an Ebay deal.  Bought the loco as parts, ad said it didn't run, and that was the cause.

I dunno, one of those things that you wish you could be there, and see whats happening. Laugh

Mike.

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Posted by MisterBeasley on Thursday, March 8, 2018 12:46 PM

It should be easy to try the other locomotive if you haven't.  That would pretty much determine if it's a wiring problem or a locomotive problem.

It takes an iron man to play with a toy iron horse. 

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Posted by BigDaddy on Thursday, March 8, 2018 12:37 PM

Ajhall
I may try to do a short video with my phone, and upload it to YouTube

With an Iphone this is easy to do.  I'm sure other smart phones are up to the task.

It never hurts to measure voltage when locos don't run.  That said, I think the reversing switch is a red herring and the problem is the decoder needs a reset.  Why?

You put the loco on the track and it runs in one direction.

  • That proves you have adequate voltage in the track
  • That proves you have adequate electrical pick up in the loco

Turn the loco 180 degrees and it doesn't go. 

  • The track voltage hasn't changed
  • The electrical pick up hasn't changed
  • You haven't told us you are pushing any other buttons or switches that we don't know about.

DCC decoders that need a reset can do weird stuff on DCC, why can't they do weird stuff on DC?  Does the other loco actually do the same thing?

 

 

Henry

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Posted by maxman on Thursday, March 8, 2018 10:58 AM

Ajhall
Would it help if I tried getting a DC power reading with a multi-meter. I've never tested for DC power, just AC circuits, but it can't be that hard to figure out.

If the goal is to check the reversing switch on the power pack, disconnect the two track feeders at the power pack terminals.  Set your meter for DC voltage, at a setting more than 12 to 14 volts DC.  Connect one lead to one of the power pack DC terminals, and the other lead to the other terminal.  Move the power pack control handle/lever to the increasing speed position.

You should see a voltage value on the meter.  It will either read a plus or minus value.  Throw the reverse switch.  The meter should now read the opposite voltage value (assuming you did not change the lever position).  If it does, this means that the reversing switch is okay.

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Posted by wjstix on Thursday, March 8, 2018 10:30 AM

I'd suggest setting up an isolated test track. I'm assuming you're using Atlas track since you mention using one of their booklets on track and wiring. Get one of the 9" terminal tracks and hook it up to one power pack's DC output. Maybe add a couple of straights on each side (either their sectional straights, or add a piece of flex track to either side).

Try the engines on the test track one at a time. Don't pick up the engine once it's on the track, just use the reverse switch on the power pack. If an engine works OK in both directions facing one way, then turn it 180 degrees and try it again. If they both work on the test track, then the error is in your wiring on the layout.

 

Stix
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Posted by Ajhall on Thursday, March 8, 2018 9:48 AM

I have a lot of testing to do when I go down to the layout later this afternoon. I may try to do a short video with my phone, and upload it to YouTube or create an Instagram account and post the link. If I can't make that work, I'll take notes on what I'm seeing as I try all the suggestions.

I want to thank everybody for taking time from your day to answer my questions. It's appreciated.

I just had a thought. Would it help if I tried getting a DC power reading with a multi-meter. I've never tested for DC power, just AC circuits, but it can't be that hard to figure out.

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Posted by Ajhall on Thursday, March 8, 2018 9:35 AM

Dave -- I just want you to know there is nothing about your post I find remotely insulting or offensive. 

dknelson
The electrons don't know where the cab or front of the locomotive is and don't care. 

That's the kind of metaphor my brain likes. 

 
Ajhall

 

Now, with the switch on the power pack to the left ("forward"), and the rear of the loco facing clockwise (left), the loco travels clockwise. When I flip it around so the front of the train is facing clockwise (left), nothing happens. When I move the switch to the right, and the front is still facing clockwise, nothing happens. When I flip the loco again (rear facing left), it moves to the left (clockwise).

I hope the above helps, and doesn't make thing murkier.

 

 

 
Ah I think I see, although your description is a bit murky to me.  In DC forward and reverse are not related to the locomotive's front and rear, but to any thing on the track.  Instead of thinking forward and reverse think of "this way" versus "that way."
 
So if the "front" of a locomotive goes right, and you pick up the locomotive and turn it around and put it back on the track without touching the reversing switch on the power pack, it should still go right.  
 
And vice versa
 
The electrons don't know where the cab or front of the locomotive is and don't care.  
 
DCC is different but not relevant to this discussion.
 
This is why you can have, say, F units back to back and they'll run in the same direction (assuming they are wired to NMRA standards) and not pull or push against each other.  
 
I do not mean to be insulting and please do not take offense.  You would benefit from a good book on DC wiring.  Linn Westcott wrote one for Kalmbach as did Andy Sperandeo, and both are out of print.  Atlas has published books on DC wiring ( with an emphasis on wiring that matches their commercial products, but very good nonetheless) for decades and theirs is still in print.  I think all will be more clear if you read up on DC wiring.
 
Dave Nelson
 
 

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